1PJ9 image
Deposition Date 2003-06-02
Release Date 2004-02-03
Last Version Date 2024-11-06
Entry Detail
PDB ID:
1PJ9
Keywords:
TRANSFERASE
Title:
Bacillus circulans strain 251 loop mutant 183-195
Biological Source:
Source Organism:
Bacillus circulans (Taxon ID: 1397)
Host Organism:
Escherichia coli
Method Details:
Experimental Method:
X-RAY DIFFRACTION
Resolution:
2.00 Å
R-Value Free:
0.17
R-Value Work:
0.15
R-Value Observed:
0.15
Space Group:
P 21 21 21
1PJ9 validation report
Macromolecular Entities
Structures with similar UniProt ID
Protein Blast
Polymer Type:polypeptide(L)
Molecule:Cyclomaltodextrin glucanotransferase
Gene (Uniprot):cgt
Mutagens:T185S, T186Y, N188D, K192R
Chain IDs:A
Chain Length:686
Number of Molecules:1
Biological Source:Bacillus circulans
UniProt ID:P43379 Pfam ID:PF00128, PF02806, PF01833, PF00686 EC:2.4.1.19
Ligand Molecules
ACY
CA
GLC
MPD
Peptide-like Molecules
PRD_900001
PRD_900009
Primary Citation
Improved thermostability of bacillus circulans cyclodextrin glycosyltransferase by the introduction of a salt bridge
PROTEINS: STRUCT.,FUNCT.,GENET. 54 128 134 (2004)
PMID: 14705029 DOI: 10.1002/prot.10516

Abstact

Cyclodextrin glycosyltransferase (CGTase) catalyzes the formation of cyclodextrins from starch. Among the CGTases with known three-dimensional structure, Thermoanaerobacterium thermosulfurigenes CGTase has the highest thermostability. By replacing amino acid residues in the B-domain of Bacillus circulans CGTase with those from T. thermosulfurigenes CGTase, we identified a B. circulans CGTase mutant (with N188D and K192R mutations), with a strongly increased activity half-life at 60 degrees C. Asp188 and Arg192 form a salt bridge in T. thermosulfurigenes CGTase. Structural analysis of the B. circulans CGTase mutant revealed that this salt bridge is also formed in the mutant. Thus, the activity half-life of this enzyme can be enhanced by rational protein engineering.

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Protein

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Disease

Primary Citation of related structures
1CDG